I see the Bills as having a great chance to make a crazy run and win a Super Bowl (or maybe 2) sometime in the next few years, but I don't see a dynasty sort of team.
I think McDermott and the Bills will most resemble the Steelers of the past 15 years. Seemingly always in it, but never really seen as THE team to beat. I mean, the Steelers are unbeaten but all you hear is "yeah, butt" from commentators. Nobody is saying they aren't a great team, but it doesn't seem like they are getting the hype or attention that an unbeaten team ought to.
If the Bills have their type of run for 15 years, winning a SB or 2, I'll take it, though!